The ability to walk is one of the fundamental attributes of human beings. However, with advancing age this ability is modified by a combination of physiological and pathological aging.These changes mainly involve an irregularity of the pitch, reducing the length of the stride, instability and a decrease in walking speed (Beauchet et al., 2002). Tinetti, Speecheley, Ginter (1988, from Ch Wider, F. Vingerhoets, J Bogousslavsky, 2005) show that 20-30% of heathly older fall each year and state that one of these falls, 25% result in injuries with significant effect and 5% a fracture. In addition to the risk of fracture fear of falling exists in many older people even before a drop in effective (Recommandation of HAS, 2005).In France, about 9 000 deaths of people aged over 65 are associated each year with a fall and this association increases rapidly with advancing age in both sexes. It is therefore important in terms of public health, learn to recognize the gait disturbance, to prevent and to make adequate assessments to reduce the risk of falls. Tools exist to assess the risk of falling. Some are comprehensive but time-consuming and are generally discarded in favour of other simpler tests (test of Tinetti or get up and go test). However, the listing of these lacks precision, particularly in terms of duration single timer.To overcome these biases, innovative technology solutions seem to be a good way. In this study, the investigators will use the motorized go-cart developed by INRIA, entitled ANG (for Assisted Navigation Guide), to obtain more reliable and accurate measurements of parameters such as walking speed and direction. Thus, the investigators set the main objective, to compare a standard evaluation of the process to a technology assessment, in participants aged 65 to 86 years. And as secondary objectives : evaluate the acceptance of using go-cart ANG in the elderly, develop an index of walking and test the feasibility of detecting a weakness of the knee joint by ANG undetected at clinic.

Inclusion Criteria:

• men and women aged between 65 and 86 years
• participants with no locomotor disability hindering the implementation of the protocol
• participants with no global cognitive impairment (MMSE score <24) (Folstein et al. 1975), or arguments in favor of the following diagnoses : probable Alzheimer's disease according to the criteria of the NINCDS-ADRDA, major depressive episode according to DSM-IV-R
• participant with no apathy according to diagnostic criteria for apathy (Robert, Onyike et al. 2009)
• participants recipients of social security
• signature of informed consent.

Exclusion Criteria:

• impossibility of carrying out the experimental protocol because of a mobility impairment